The Potential Role of Antigen Priming In Increasing the Overall Antimicrobial Resistance in Captive Silver Foxes

Objective: We hypothesized antigenic priming should stimulate the humoral and cellmediated adaptive immunity, further improved by vegetal extracts, alleviating the immune suppression induced by captivity stress in silver foxes. Material and Methods: One of two groups of adult silver foxes was sc primed and boosted 7 days later with a 5% SRBC suspension. Serum antibody titers (hemagglutination test) and circulating immune complexes levels (4.2% PEG precipitation) were quantified and ln of the antibody titers were calculated seven days later. An in vitro blast transformation test was carried out on blood samples using alcoholic extracts of C. officinalis, A. montana, S.officinale, Echinaceea spp. and immune stimulating compounds and glucose consumption was evaluated. The significance of the differences was interpreted by Student’s t-test. Results: Cells grew better in primed foxes versus the unprimed individuals (68.8±9.88 and 17.49±22.9). The primed animals reacted significantly (p< 0.001-p< 0.01) better to vegetal extracts (C. officinalis, E. angustifolia) and to thymus extract, selenium salts and bovine tuberculin. Anti-SRBC antibodies were highly variable (0.69 - 5.54). Conclusion: SRBC exerted a positive effect on both humoral and cell-mediated immune responses in silver foxes, supporting the enhancement of antimicrobial defense by booster vaccination and immune stimulating therapy.